Studies on Antigen-binding Activity of Macroglobulin Antibody Subunits and Their Enzymatic Fragments

摘要: Abstract To gain insight into reasons for the presence of only five combining sites in γM antibodies, studies were undertaken to determine number antigen-binding on subunits and Fabµ fragments a rheumatoid factor anti-γ-globulin from patient with "mixed cryoglobulins." The contained both κ λ light chains reacted human rabbit γG. Combining ratios determined by quantitatively determining amount complex formation analytical ultracentrifugation. Each monomeric subunit had one effective site, there no inactive subunits. All 3.7 S fragments, prepared trypsin digestion subunits, active each at least binding site per fragment. These results indicate that are 10 potential intact molecule although available antigen binding. Studies performed also nature cross-reaction this antibody experiments showed formed their was same whether consisted γG alone, or mixture two. Since is evidence which combine species γG, appear resemble those other cross-reacting systems may be occupied either antigen. In contrast excellent activity little